A badly decomposed body bears all the signs of a ritualistic killing. Sam follows the clues into the world of the occult.

Sam cannot state for certain whether PC Johns committed suicide or whether he fell, and investigating officers are beginning to believe that something is being covered up. Sam receives a suspicious package in the post and the bomb squad are called in.

Vietnamese refugee Tran tells the harrowing story of her family's nightmare journey across the South China Seas. The complex story of the guilt and fatherhood ends in tragedy, and forces Sam to face some of her own demons concerning her father.

Forensic Pathologist Dr Samantha Ryan moves back to Cambridge from London to take up a consultant's post at The Park Teaching Hospital. Sam's first case is the tragic death of a six-year-old girl, Sarah Crew, who is thought to have fallen from a rope swing over a river and drowned. But when Sam finds evidence of previous physical abuse, Inspector Tom Adams begins a murder investigation.

Dr Sam Ryan is called to the scene of the murder of Mark James, a young man whose badly decomposed body cannot hide the signs of a ritual element to the killing: there is an upside-down cross scored on his back and a ligature around his neck. Then when a second murder follows, Sam follows the trail of clues into the world of the occult.

When a death occurs in police custody, the footprints of the man who was sharing his cell are found all over the body. It looks like an open and shut case for Dr Sam Ryan. But just as the investigation appears to be over, Sam receives a note written on police notepaper that re-opens the case. It seems that the real culprit may have been a police officer, but which one?